Request for review: NPE when using Nimbus with a TableCellRenderer returning null. (original) (raw)

Clemens Eisserer linuxhippy at gmail.com
Fri May 10 22:01:14 UTC 2013

Hi Alexander,

Could you send a code snippet from your application that reproduces the NPE? I think we should investigate first why the JTable.prepareRenderer() returns null in this case.

Sorry for the lag - I have been on vacation. I'll prepare something tomorrow.

Regards, Clemens

Thanks, Alexandr.

On 4/18/2013 9:37 AM, Miguel Muñoz wrote:

JTable.prepareRenderer() should never return null. There's nothing in the API to suggest that null is a valid return value. I have found (and reported) at least one bug in Nimbus where it returns a null renderer when the column class is Icon. I think that's fixed, but I wouldn't be surprised if there are others. — Miguel Muñoz

On Apr 16, 2013, at 7:55 AM, Alexander Scherbatiy wrote: On 4/13/2013 2:19 PM, Clemens Eisserer wrote:

Hi, When testing a legacy application which was using Metal LnF previously with Nimbus I ran into the following problem: Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at javax.swing.plaf.synth.SynthTableUI.paintCell(SynthTableUI.java:685) at javax.swing.plaf.synth.SynthTableUI.paintCells(SynthTableUI.java:581) ...... the code in question is: TableCellRenderer renderer = table.getCellRenderer(row, column); Component component = table.prepareRenderer(renderer, row, column); Color b = component.getBackground();

Could you check that returning the null component is the correct behavior in this case? So there is no the real bug that does not allow to return the right component.

I've written a patch to simply check for "component" to be non-null: http://cr.openjdk.java.net/~ceisserer/nimbusnpe/ <http://cr.openjdk.java.net/%7Eceisserer/nimbusnpe/> Unfortunately I don't have a bug number, as the old bug-submission There are 2 issues with the NPE in paintCell chain call in JTable: 6582564 JTable with rowHeader and sorting given NPE when inserting a new row http://bugs.sun.com/viewbug.do?bugid=6582564 6429812 NPE after calling JTable.updateUI() when using a header renderer + XP L&F http://bugs.sun.com/viewbug.do?bugid=6429812 This issue is different so I can create the new one. Thanks, Alexandr. system seems to be dead. Please let me know what you think. Regards, Clemens ------------------------------------------- Miguel Muñoz SwingGuy1024 at yahoo.com <mailto:SwingGuy1024 at yahoo.com> 323/225-7285 ------------------------------------------- /The Sun, with all those planets revolving around it and dependent on it, can still ripen a vine of grapes like it had nothing else to do in the world./ -- Galileo ------------------------------------------- / / /There are seven sins in the world./ / Wealth without work./ ///Pleasure without conscience./ ///Knowledge without character./ ///Commerce without morality./ ///Science without humanity./ ///Worship without sacrifice./ ///Politics without principle./// / / -- Mohandas Gandhi ------------------------------------------- /If tyranny and oppression come to this land, it will come in the guise of fighting a foreign enemy./ -- James Madison

More information about the swing-dev mailing list